HARRISBURG - Scientists, politicians and public health advocates around the world can't decide whether it's a good idea to put fluoride in public drinking-water supplies. State Rep. Tom Tigue, though, has made up his mind.

Fluoridating public water supplies is ``one of the least costly, most effective health care (measures) we can do,'' said Tigue, D-Hughestown.

Tigue last month reintroduced a bill to require statewide fluoridation of public water supplies. Most Luzerne County water customers won't get fluoridated tap water unless his bill goes through, he said.

The legislation sparked opposition from state and national environmental and health watchdog groups. They point out many European nations have banned the chemical from their water supplies. They cite studies that purportedly show the chemical is toxic and causes maladies ranging from bone deterioration and cancer to brown spots on teeth.

That's nonsense, according to the U.S. Centers for Disease Control. The agency - along with the state Department of Health and an array of state and national medical and dental associations - assert that fluoride is safe and beneficial. Putting the chemical in drinking water at a centralized treatment facility reduces cavities between 30 and 60 percent, according to a report by the U.S. Surgeon General's office.

"Depending on who you talk to - even in the scientific community - you're going to get a different opinion," said state Rep. Dan Surra, D-Kersey. Surra sat on the state House committee that let Tigue's bill wither on the vine without so much as a public hearing.

The committee chairman, Rep. Arthur Hershey, R-Cochranville, pointed out that versions of the bill have bounced around the Legislature since at least the late 1980s, but never passed. Hershey said Tigue's bill does not provide state assistance for fluoridation.

The CDC estimate that fluoridation costs between 68 cents and $3 per person per year, depending on service district size.

It's not worth it, even if it's free, said Bill Smedley, executive director of GreenWatch, a Williamsport-based national environmental group that has worked to stop fluoridation. Smedley cited a variety of independent studies showing fluoride causes deterioration of the thyroid gland, weakening of the immune system, internal soft-tissue damage "and makes bones toxic to themselves."

"We should let the local communities decide on their own," said Surra, who was preparing this week to introduce a competing bill to Tigue's that would make the fluoridation decision a local one.

Eleven states mandate fluoride in public drinking water, according to the CDC. They estimate 56 percent of the nation's public water customers get fluoridated tap water. That number drops to 48 percent in Pennsylvania, according to the state Department of Environmental Protection.

In Luzerne County, the percentage is far lower. That's because the Hazleton City Authority, which provided water to roughly 38,000 households in 1997, is the only public water supplier providing fluoridated water in the county.

Pennsylvania-American Water Company, by far the largest provider in the region in the Wilkes-Barre/Scranton area, is "neutral on the issue," said Joi Corrado, company spokeswoman. The company has 10 treatment facilities and 138,000 customers in the area, none of whom get fluoridated water. It will add fluoride to a given area only if all the municipalities served by that supply district request it, Corrado said.

That's not likely to happen, because it would take a coordinated effort by several municipalities, Tigue said. Most water districts cross town lines.